MAPPING COGNITIVE BRAIN-FUNCTION WITH MODEM HIGH-RESOLUTION ELECTROENCEPHALOGRAPHY

High temporal resolution is necessary to resolve the rapidly changing patterns of brain activity that underlie mental function. While electr oencephalography (EEG) provides temporal resolution in the millisecond range, which would seem to make it an ideal complement to other imagi ng modalities, traditional EEC technology and practice provides insuff icient spatial detail to identify relationships between brain electric al events and structures and functions that are visualized by magnetic resonance imaging (MRI) or positron emission tomography (PET). Recent advances overcome this problem by recording EEGs from more electrodes , by registering EEG data with anatomical information from each subjec t's MRI, and by correcting the distortion that is caused by volume con duction of EEG signals through the skull and scalp. Along with its abi lity to record how brains think when performing everyday activities in the real world, these advances make modern EEG an invaluable compleme nt to other functional neuroimaging modalities.